Field Notes

Leave it to beavers

11 min read / March 11, 2025 / By Sarah Wolfe

The underappreciated beaver plays a big role in land and water restoration

Beaver-created wetlands absorb floods, absorb carbon, and boost biodiversity. So why don’t we see more of them in Vermont? Historically, landowners have considered beavers a nuisance. But we’re discovering better ways to share the land — and the benefits.

Beavers: sustainability superheroes

Beavers are a keystone species. They got that fancy title because they engineer wetland ecosystems that sustain other plants and animals. All that engineering also helps humans. Wetlands filter water, trapping sediment and pollutants like phosphorous. By creating wetlands, beavers improve water quality throughout our watersheds.

Beaver-created wetlands also store carbon and help combat extreme weather events caused by climate change. They store and slow water during flood events. And when drought hits, beaver ponds store precious groundwater to limit the impact. Some beaver wetlands have even acted as firebreaks, slowing the spread of wildfires.

Allaire Diamond is an ecologist at VLT and a beaver believer. “Beavers play a completely unique, and critical, ecological role,” she says. “They evolved in our landscape and they shape it. We’re learning how the wetlands they create can help meet a range of challenges, from fire to drought to floods.”

Photo: a nearly four foot tall beaver dam at a conserved property in Fairfield.

Beyond the dam: how beavers create diverse wetlands

Human vs. beaver dams: what’s the difference?

When we think of beavers, we often think of dams. Beavers construct their dams with rocks, sticks, mud, and leaves, and typically build many small dams close to each other. Behind and between these dams, a wetland complex forms that includes areas of open water as well as areas dominated by herbaceous plants, shrubs, and trees. These complexes sustain diverse — and sometimes rare — water-loving plants and animals. Beaver wetlands store huge amounts of water and release it slowly, naturally maintaining downstream water levels and temperatures and helping recharge groundwater.

The sediment trapped in beaver wetlands stores carbon that would otherwise contribute to climate change. (The amount of carbon sequestered varies based on the size and history of the wetland.) Wetland plants provide additional carbon sequestration by pulling and storing carbon from the atmosphere.

Beaver dams differ from human-made ones in several ecologically significant ways. Human-created dams are larger and less porous, leading to stagnant water upstream and erosion downstream. They can be built with earth, stone, concrete, metal, or other materials. Removing human dams can help restore a watershed to its natural state. Creating space for beavers to build their own dams can also support watershed restoration.

Photo: a beaver complex in Dorset, VT at the headwaters of Otter Creek showing four dams, a lodge, and numerous canals. VLT removed a human-made dam further downstream (off the bottom of this image) to help this beaver complex continue to expand and provide benefits throughout the watershed.

Canals expand wetland complexity and benefits

Dams are just one tool in beavers’ engineering toolkit. As the water level rises and the wetland grows, beavers also dig canals to reach new food sources. (It’s far easier to swim along the canals than to walk along land with those webbed hind feet!) Meanwhile, more wetland plants and animals flourish as the canals expand the wetland complex.

Along the shores of the wetland, beavers are busy gathering wood. They cut large trees to harvest branches and gnaw twigs from shoreline saplings and shrubs. Where they work, new growth emerges. The edges of a beaver pond become home to shrubby and leafy plants and saplings. This creates a diverse habitat for birds and other semi-aquatic creatures.

“The beaver is working as a forest manager, selectively managing wood over time,” Allaire says. “You’ll see stems that have been cut in different years based on the age of the stump. Beavers can create a diverse woodland around the pond with mature trees and new growth forming.”

Photo: a beaver-made canal meanders through Atlas Bogs.

“We want to become landscape engineers ourselves. While we lack the beaver’s natural instincts for habitat creation, we are pretty good students. On our conserved properties, we’re trying to think creatively about ways to use the beaver’s tricks of the trade for long-term ecological impacts.”

– Allaire Diamond, VLT Ecologist

Where have all the beavers gone?

Given all the benefits beavers provide, it may be surprising there aren’t more of their dams filling our landscape today. As Europeans colonized America, trappers nearly eliminated beavers in some areas by the 1800s after trapping and killing them for their prized fur. Though they have rebounded significantly, today’s beavers are still a fraction of what once roamed the waterways. Vermont has a healthy population, but many areas of potential beaver habitat sit unoccupied.

Today, beavers’ biggest threat is habitat loss. Our cities, towns, and farms have taken over much of the land that beavers once cultivated (in Vermont, this is partly because towns and settlements formed in a landscape that had just recently been emptied of beavers). Beaver dams can bring water close to active farm fields and roads, causing conflicts with human infrastructure and activities.

We think of beavers as nomadic, appearing in a new spot seemingly overnight and then disappearing again some months or years later. But those tendencies are partly a result of human interference. A beaver complex can survive for hundreds of years, supporting uninterrupted generations of beavers. The longer a beaver wetland complex exists, the more dynamic and diverse it becomes, with benefits spreading throughout the watershed.

Photo: an old beaver chew in Atlas Bogs provides a home for an entire tiny ecosystem.

Can we partner with beavers as mutual land stewards?

In recent years, humans have come a long way toward understanding how to make peace with beavers. Today a core part of VLT’s land restoration work is to create the conditions for beavers to regrow and repopulate. We want them to come in and do many of the things we’re trying to do — but better.

There are many ways to encourage these toothy land stewards into areas that would benefit most from their work, without causing problems for landowners. Below, we share three strategies we’ve seen work well: coexist, copy, and champion.

1. Coexist

Where possible, avoid disrupting beavers. Before taking down a beaver dam, consider whether it’s necessary. Even short-term beaver dams can provide benefits. If a recent dam is washed downstream, the green wood can lodge in downstream dams or streambanks and grow new saplings, anchoring soil. The longer the beaver works, the greater the benefits to the entire watershed.

Beaver flow devices

When beaver dams flood roads or active farm fields, landowners can install beaver flow devices to manage beaver activity without relocation. They can be installed inside an existing dam or in a location beavers like to dam. A large pipe runs through the stream underwater, ensuring water flow but hiding the telltale trickle of water that spurs beavers to action. A fence on the pond side of the pipe keeps beavers from plugging it.

We installed a “Beaver Deceiver” at Brewster Uplands in 2023. Local beavers had been damming a culvert and flooding a road across the property. If you visit the property today, you’ll only see evidence of happy beavers. The beaver deceiver is underwater, and the beavers still have the entire wetland to work and build in.

Photo: Skip Lisle, founder of Beaver Deceivers, LLC, pulling the new Beaver Deceiver into the water at Brewster Uplands.

2. Copy

Take a few pages from the beaver’s forest management playbook: Plant beaver-friendly trees and shrubs along river corridors to establish riparian buffers and provide food sources for future beavers. Selectively manage existing shoreline plants to encourage diversity and control erosion.

Beaver dam analogs

Near a stream? Try a little beaver-inspired dam building. “Beaver dam analogs” can rebuild healthy stream channels and bring water out to floodplains, begin to reestablish a wetland in a landscape without beavers, or even attract beavers to take up the work. They can provide some benefits that a beaver dam or beaver complex would, such as slowing floodwaters and trapping sediment and pollutants.

We’ve installed beaver dam analogs at several sites, including Colchester and Dorset, where we first removed human-made dams. With these natural woody structures in the streams, we’re seeing the areas start to become more flood resilient and return to their natural states.

“We want to become landscape engineers ourselves,” Allaire says. “While we lack the beaver’s natural instincts for habitat creation, we are pretty good students. On our conserved properties, we’re trying to think creatively about ways to use the beaver’s tricks of the trade for long-term ecological impacts.”

Photo: a beaver dam analog at Crooked Creek in Colchester.

3. Champion

We’re beginning to integrate beavers’ mindset and methods into our ecological thinking, knowing these animals still have so much to teach us. So, help us increase their profile! We’re working on spreading the word about the myriad ways beavers can support our land and water. Here are some ways you can be a beaver champion:

Tell their story. Share a fun fact or a positive story about what beavers can do with friends and family.
Ask questions. If you hear about a beaver causing challenges for someone’s property, learn more about what those challenges are. Could they be avoided with a beaver deceiver? Are there changes that could be made to the property to allow coexistence?
Be curious. Beavers aren’t the only landscape engineers around. Other creatures often considered pests, like woodchucks, have ecological benefits on the landscape. Being curious about our animal neighbors will help us learn to live together.

Photo: a beaver dam complex in Athens, VT.

Eager to get started?

Do you have a location that might benefit from a beaver deceiver or a beaver dam analog? Curious about how to invite beavers to your property? We may be able to support your efforts. Reach out to our ecologist and local beaver champion, Allaire Diamond, to learn more.